1. Technical Field
The embodiments herein generally relate to photovoltaic (PV) solar panels, and more particularly to techniques to ensure safe interaction with PV solar panels.
2. Description of the Related Art
PV solar panels are an important source of electrical power. Large, megawatt arrays with PV panels numbering in the tens of thousands are increasingly common. A typical PV panel is organized as a series connection of individual PV cells. A common configuration is 72 PV cells per panel. A typical PV cell operating voltage under full illumination is approximately 0.7 V. An illuminated PV panel with 72 direct current (DC) PV cells will therefore have an output voltage of approximately 50 volts DC. PV panels are typically connected in series to form a panel “string”. In a DC PV panel system, the output of the PV panel string could connect to a central inverter which converts the DC power of the PV panels into AC power suitable for the electrical grid. Typically, there are between five and twenty PV panels in a panel string producing a combined voltage of several hundred volts.
PV panels produce power whenever they are illuminated. As described above, the voltages on a string could reach hazardous levels of hundreds of volts. These voltages could be a safety hazard during PV panel installation and maintenance. If the PV panels are mounted to a roof or integrated into building structures, these voltages can also represent a hazard during emergency operations such as fire fighting since the PV panels will continue to generate voltage even when the PV installation is disconnected from the electrical grid. Accordingly, there remains a need for a technique to allow for safer interaction with PV solar panels.